The need for a wide band, vertically-polarized antenna for high frequency communication systems has led to the development of logarithmically periodic antennas. The log periodic bent zig zag antenna is one of the first log periodic structures introduced which provided vertical polarization and frequency independent performance over a ground plane. The maximum height of the log periodic zig zag antenna is a quarter of the lowest operating wavelength, making it ideal for low VHF communication applications.
"The Bent Log Periodic Zig Zag Antenna" by J. W. Greiser, a supplement to Interim Engineering Report No. 4 for Broadband Wide Aperture Radio Location Antenna System, is a technical report of the Antenna Laboratory, University of Illinois, 31 May 1962. This report provides extensive analysis of log periodic antennas with measured pattern and impedance data. The physical parameters of the bent log periodic zig zag antennas are disclosed beginning at page 19 with reference to FIG. 4, page 20. The vertical wires are the radiators when they are in resonance and the horizontal wires are phasing stubs. Typical of these antennas parameters are the vertical length, which is the distance from a point of origin to the tip of the longest element and the angles from the axis passing through the origin to the tips of the radiating elements and phasing stubs. The plane of the horizontal stubs is also inclined at an angle and passes through the origin. Numerous other parameters exist for the basic antenna which are fully disclosed in the prior art, as for example at pages 19-29 of the Greiser report.